Biomechanical factors that regulate outflow facility in human eyes. Elevated intraocular pressure (IOP) is the primary risk factor for optic nerve damage in glaucoma. The central hypothesis to be tested within this research is that periodic changes in IOP impact regulatory mechanisms that affect fluid flow through the conventional outflow pathway. Experiments will be performed using the anterior segment perfusion model using post mortem human eyes. The specific aims are as follows: 1) To examine mechanisms by which diurnal oscillations in aqueous secretion affect conventional outflow facility. 2) To investigate how pulsatile intraocular pressure influences mechanisms that regulate conventional outflow facility. For both aims, control and experimental groups will be compared over time, to observe how these physiological stressors affect the following endopints: - Outflow facility/lOP, - mRNA levels of trabecular meshwork cells ex-vivo, - protein secretion by conventional outflow cells, and - pore density in the inner wall of Schlemm's canal. The experiments outlined in this proposal will examine the physiological, morphological, and biochemical effects of these two physiologically relevant mechanical stressors on the anterior segment perfusion